P2: Energy transfer by heating

Question 1

thermal conductivity

Answer 1

thermal conductivity of a material tells you how quickly energy is transferred through it by thermal conduction

Question 2

insulating buildings

Answer 2

lower thermal conductivity = lower rate of heat loss
factors that affect thermal conductivity in a house are : the thickness of the walls and roof and their thermal conductivity the thermal conductivity can be reduced by using thermal insulators

Question 3

infrared radiation

Answer 3

part of the electromagnetic spectrum all objects emit and absorb infrared radiation the higher the temperature of an object the more infrared radiation it emits in a given time a objects temperature will increase if it absorbs infrared radiation at a higher rate then it emits
infrared radiation emitted = infrared radiation absorbed

Question 4

black body

Answer 4

theoretical object that obsorbs 100% of the radiation that falls on it a perfect black body would not reflect or transmit any radiation and would be a perfect emitter of radiation

Question 5

specific heat capacity

Answer 5

when a substance is heated or cooled the temperature change depends on the substances mass the type of material and how much energy is transferred to it. every material has a specific heat capacity- the amount of energy needed to raise the temperature of 1kg of the substance by 1 degrees

Question 6

specific heat capacity equation

Answer 6

change in thermal energy = mass X specific heat capacity X temperature change